Today's cellular networks for wireless communication are required to support a large variety of content. Some examples of such content that is exchanged in a communication network comprise voice calls, video calls, small and large data files, streaming of audio and video. In addition to these forms of content, the networks transfer this content at various times during the day and night. This typically leads to a highly fluctuating traffic volume during day and night hours. Still further, the traffic volume also differs from one cell to the other.
Thus, when planning and designing capacity in a cellular network, the different peaks of traffic volume or load in the different cells in the network are taken into account. This is done in order to provide a reliable communication network that will, to a large extent, provide requested communication services to all the customers in each cell, also during peak hour traffic.
Because the communication networks are designed to provide or support requested communication services to all the customers in each cell, also during the peak hours, substantial capacity exists in the networks which remains unused during off-peak hours. During off-peak hours, the traffic volume or load is smaller, which means that the capacity which remains unused is wasted. This increases the cost of operating the communication network.
In order to smooth out the traffic volume or load over time, the radio network can control caching of information communicated which need not be delivered in real-time.
In PCT/IB2011/003074 discloses to use a client caching that is network controlled, which is also called optimized scheduled delivery architecture for delivering delay-tolerant content. This transfer to mobile terminals takes into account the load in the communication network. A network cache having a direct interface to the radio access network can initiate transfer of data to the client when the radio conditions are suitable. The client cache can be used by multiple applications and is owned by the end-user, rather than by an operator. An interface is defined between the two caches for delayed data transfer on both data plane and control plane level. The interface allows both the network cache and client cache to control the data transfer. This solution enables transfer of delay-tolerant content to clients whenever is optimal from a radio and client perspective.
Since the network load is dynamic, the load at the time of scheduled delivery may look different from the one as determined by the network cache.
For this reason a complementary approach for optimized scheduled delivery can be preferred at times.